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Scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and aerosol time-of-flight mass spectrometry (ATOFMS) single particle analysis of metallurgy plant emissions
2016
Arndt, J. | Deboudt, K. | Anderson, A. | Blondel, A. | Eliet, S. | Flament, P. | Fourmentin, M. | Healy, R.M. | Savary, V. | Setyan, A. | Wenger, J.C.
The chemical composition of single particles deposited on industrial filters located in three different chimneys of an iron-manganese (Fe–Mn) alloy manufacturing plant have been compared using aerosol time-of-flight mass spectrometry (ATOFMS) and scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDX). Very similar types of particles were observed using both analytical techniques. Calcium-containing particles dominated in the firing area of the sintering unit, Mn and/or Al-bearing particles were observed at the cooling area of the sintering unit, while Mn-containing particles were dominant at the smelting unit. SEM-EDX analysis of particles collected downstream of the industrial filters showed that the composition of the particles emitted from the chimneys is very similar to those collected on the filters. ATOFMS analysis of ore samples was also performed to identify particulate emissions that could be generated by wind erosion and manual activities. Specific particle types have been identified for each emission source (chimneys and ore piles) and can be used as tracers for source apportionment of ambient PM measured in the vicinity of the industrial site.
Show more [+] Less [-]Chemical composition and source apportionment of size fractionated particulate matter in Cleveland, Ohio, USA
2016
Kim, Yŏng-ho | Krantz, Q Todd | McGee, John | Kovalcik, Kasey D. | Duvall, Rachelle M. | Willis, Robert D. | Kamal, Ali S. | Landis, Matthew S. | Norris, Gary A. | Gilmour, M Ian
The Cleveland airshed comprises a complex mixture of industrial source emissions that contribute to periods of non-attainment for fine particulate matter (PM2.5) and are associated with increased adverse health outcomes in the exposed population. Specific PM sources responsible for health effects however are not fully understood. Size-fractionated PM (coarse, fine, and ultrafine) samples were collected using a ChemVol sampler at an urban site (G.T. Craig (GTC)) and rural site (Chippewa Lake (CLM)) from July 2009 to June 2010, and then chemically analyzed. The resulting speciated PM data were apportioned by EPA positive matrix factorization to identify emission sources for each size fraction and location. For comparisons with the ChemVol results, PM samples were also collected with sequential dichotomous and passive samplers, and evaluated for source contributions to each sampling site. The ChemVol results showed that annual average concentrations of PM, elemental carbon, and inorganic elements in the coarse fraction at GTC were ∼2, ∼7, and ∼3 times higher than those at CLM, respectively, while the smaller size fractions at both sites showed similar annual average concentrations. Seasonal variations of secondary aerosols (e.g., high NO3− level in winter and high SO42− level in summer) were observed at both sites. Source apportionment results demonstrated that the PM samples at GTC and CLM were enriched with local industrial sources (e.g., steel plant and coal-fired power plant) but their contributions were influenced by meteorological conditions and the emission source's operation conditions. Taken together the year-long PM collection and data analysis provides valuable insights into the characteristics and sources of PM impacting the Cleveland airshed in both the urban center and the rural upwind background locations. These data will be used to classify the PM samples for toxicology studies to determine which PM sources, species, and size fractions are of greatest health concern.
Show more [+] Less [-]Characterization and source apportionment of size-segregated atmospheric particulate matter collected at ground level and from the urban canopy in Tianjin
2016
Wang, Jiao | Zhou, Ming | Liu, Bao-shuang | Wu, Jian-hui | Peng, Xing | Zhang, Yu-fen | Han, Su-qin | Feng, Yin-chang | Zhu, Tan
To investigate the size distributions of chemical compositions and sources of particulate matter (PM) at ground level and from the urban canopy, a study was conducted on a 255 m meteorological tower in Tianjin from December 2013 to January 2014. Thirteen sets of 8 size-segregated particles were collected with cascade impactor at 10 m and 220 m. Twelve components of particles, including water-soluble inorganic ions and carbonaceous species, were analyzed and used to apportion the sources of PM with positive matrix factorization. Our results indicated that the concentrations, size distributions of chemical compositions and sources of PM at the urban canopy were affected by regional transport due to a stable layer approximately 200 m and higher wind speed at 220 m. The concentrations of PM, Cl− and elemental carbon (EC) in fine particles at 10 m were higher than that at 220 m, while the reverse was true for NO3− and SO42−. The concentrations of Na+, Ca2+, Mg2+, Cl− and EC in coarse particles at 10 m were higher than that at 220 m. The size distributions of major primary species, such as Cl−, Na+, Ca2+, Mg2+ and EC, were similar at two different heights, indicating that there were common and dominant sources. The peaks of SO42−, NH4+, NO3− and organic carbon (OC), which were partly secondary generated species, shifted slightly to the smaller particles at 220 m, indicating that there was a different formation mechanism. Industrial pollution and coal combustion, re-suspended dust and marine salt, traffic emissions and transport, and secondary inorganic aerosols were the major sources of PM at both heights. With the increase in vertical height, the influence of traffic emissions, re-suspended dust and biomass burning on PM weakened, but the characteristics of regional transport from Hebei Province and Beijing gradually become obvious.
Show more [+] Less [-]Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers
2016
Ayrault, Sophie | Catinon, Mickaël | Boudouma, Omar | Bordier, Louise | Agnello, Gregory | Reynaud, Stéphane | Tissut, Michel
Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg−1 dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.
Show more [+] Less [-]Chemical composition of PM10 and its in vitro toxicological impacts on lung cells during the Middle Eastern Dust (MED) storms in Ahvaz, Iran
2016
Naimabadi, Abolfazl | Ghadiri, Ata | Idani, Esmaeil | Babaei, Ali Akbar | Alavi, Nadali | Shirmardi, Mohammad | Khodadadi, Ali | Marzouni, Mohammad Bagherian | Ankali, Kambiz Ahmadi | Rouhizadeh, Ahmad | Goudarzi, Gholamreza
Reports on the effects of PM10 from dust storm on lung cells are limited. The main purpose of this study was to investigate the chemical composition and in vitro toxicological impacts of PM10 suspensions, its water-soluble fraction, and the solvent-extractable organics extracted from Middle Eastern Dust storms on the human lung epithelial cell (A549). Samples of dust storms and normal days (PM10 < 200 μg m⁻³) were collected from December 2012 until June 2013 in Ahvaz, the capital of Khuzestan Province in Iran. The chemical composition and cytotoxicity were analyzed by ICP- OES and Lactase Dehydrogenase (LDH) reduction assay, respectively. The results showed that PM10 suspensions, their water-soluble fraction and solvent-extractable organics from both dust storm and normal days caused a decrease in the cell viability and an increase in LDH in supernatant in a dose–response manner. Although samples of normal days showed higher cytotoxicity than those of dust storm at the highest treated dosage, T Test showed no significant difference in cytotoxicity between normal days and dust event days (Pvalue > 0.05). These results led to the conclusions that dust storm PM10 as well as normal day PM10 could lead to cytotoxicity, and the organic compounds (PAHs) and the insoluble particle-core might be the main contributors to cytotoxicity. Our results showed that cytotoxicity and the risk of PM10 to human lung may be more severe during dust storm than normal days due to inhalation of a higher mass concentration of airborne particles. Further research on PM dangerous fractions and the most responsible components to make cytotoxicity in exposed cells is recommended.
Show more [+] Less [-]VOCs emission rate estimate for complicated industrial area source using an inverse-dispersion calculation method: A case study on a petroleum refinery in Northern China
2016
Wei, Wei | Lv, Zhaofeng | Yang, Gan | Cheng, Shuiyuan | Li, Yue | Wang, Litao
This study aimed to apply an inverse-dispersion calculation method (IDM) to estimate the emission rate of volatile organic compounds (VOCs) for the complicated industrial area sources, through a case study on a petroleum refinery in Northern China. The IDM was composed of on-site monitoring of ambient VOCs concentrations and meteorological parameters around the source, calculation of the relationship coefficient γ between the source's emission rate and the ambient VOCs concentration by the ISC3 model, and estimation of the actual VOCs emission rate from the source. Targeting the studied refinery, 10 tests and 8 tests were respectively conducted in March and in June of 2014. The monitoring showed large differences in VOCs concentrations between background and downwind receptors, reaching 59.7 ppbv in March and 248.6 ppbv in June, on average. The VOCs increases at receptors mainly consisted of ethane (3.1%–22.6%), propane (3.8%–11.3%), isobutane (8.5%–10.2%), n-butane (9.9%–13.2%), isopentane (6.1%–12.9%), n-pentane (5.1%–9.7%), propylene (6.1–11.1%) and 1-butylene (1.6%–5.4%). The chemical composition of the VOCs increases in this field monitoring was similar to that of VOCs emissions from China's refineries reported, which revealed that the ambient VOCs increases were predominantly contributed by this refinery. So, we used the ISC3 model to create the relationship coefficient γ for each receptor of each test. In result, the monthly VOCs emissions from this refinery were calculated to be 183.5 ± 89.0 ton in March and 538.3 ± 281.0 ton in June. The estimate in June was greatly higher than in March, chiefly because the higher environmental temperature in summer produced more VOCs emissions from evaporation and fugitive process of the refinery. Finally, the VOCs emission factors (g VOCs/kg crude oil refined) of 0.73 ± 0.34 (in March) and 2.15 ± 1.12 (in June) were deduced for this refinery, being in the same order with previous direct-measurement results (1.08–2.65 g VOCs/kg crude oil refined).An inverse-dispersion calculation method was applied to estimate VOCs emission rate for a petroleum refinery, being 183.5 ton/month (March) and 538.3 ton/month (June).
Show more [+] Less [-]Urban PM2.5 oxidative potential: Importance of chemical species and comparison of two spectrophotometric cell-free assays
2016
Visentin, M. (Marco) | Pagnoni, Antonella | Sarti, Elena | Pietrogrande, Maria Chiara
Oxidative potential (OP) of particulate matter (PM) − defined as the capacity of PM to oxidize target molecules generating reactive oxygen species (ROS) − has been proposed as a more health relevant metric than PM mass. In this study two cell-free methods were used to assess the OP of PM filters collected at an urban site and to evaluate correlation with PM mass and PM composition.Among the different assays existing, two inexpensive and user-friendly methods were used both based on spectrophotometric measurements of depletion rate of target reagents oxidized by redox-active species present in PM. One assay measures the consumption of dithiothreitol (OPDTT) and the other the ascorbate (OPAA).Although both assays respond to the same redox-active species, i.e., quinones and transition metals, no correlations were found between OPDTT and OPAA responses to compounds standard solutions as well as to ambient samples. When expressed in relation to air volume, OPDTT m−3 strongly correlates with PM2.5 mass whereas no correlation was found for OPAA m−3 with PM2.5. When expressed on mass basis, both OPDTT μg−1 and OPAA μg−1 show a strong dependence on the sample composition, with higher OP for summer samples. OPDTT m−3 were highly correlated with the determined metals (Cu, Zn, Cr, Fe, Ni, Mn) whereas OPAA m−3 showed only moderate correlation with Cu and Mn.Thus, the two assays could potentially provide complementary information on oxidative potential characteristic of PM. Consequently, the combination of the two approaches can strengthen each other in giving insight into the contribution of chemical composition to oxidative properties of PM, which can subsequently be used to study health effects.
Show more [+] Less [-]Composition and depth distribution of hydrocarbons in Barataria Bay marsh sediments after the Deepwater Horizon oil spill
2016
Dincer Kırman, Zeynep | Sericano, José L. | Wade, Terry L. | Bianchi, Thomas S. | Marcantonio, Franco | Kolker, Alexander S.
In 2010, an estimate 4.1 million barrels of oil were accidentally released into the Gulf of Mexico (GoM) during the Deepwater Horizon (DWH) Oil Spill. One and a half years after this incident, a set of subtidal and intertidal marsh sediment cores were collected from five stations in Barataria Bay, Louisiana, USA, and analyzed to determine the spatial and vertical distributions and source of hydrocarbon residues based on their chemical composition. An archived core, collected before the DWH oil spill from the same area, was also analyzed to assess the pre-spill hydrocarbon distribution in the area. Analyses of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and stable carbon isotope showed that the distribution of petroleum hydrocarbons in Barataria Bay was patchy and limited in areal extent. Significant TPH and ΣPAH concentrations (77,399 μg/g and 219,065 ng/g, respectively) were detected in the surface sediments of one core (i.e., core A) to a depth of 9 cm. Based on a sedimentation rate of 0.39 cm yr−1, determined using 137Cs, the presence of anthropogenic hydrocarbons in these sediment core deposited ca. 50 to 60 years ago. The historical background hydrocarbon concentrations increased significantly at the sediment surface and can be attributed to recent inputs. Although the oil present in the bay's sediments has undergone moderate weathering, biomarker analyses performed on core A samples likely indicated the presence of hydrocarbons from the DWH oil spill. The effects of oiling events on Barataria Bay and other marsh ecosystems in this region remain uncertain, as oil undergoes weathering changes over time.
Show more [+] Less [-]Trace elements in hazardous mineral fibres
2016
Both occupational and environmental exposure to asbestos-mineral fibres can be associated with lung diseases. The pathogenic effects are related to the dimension, biopersistence and chemical composition of the fibres. In addition to the major mineral elements, mineral fibres contain trace elements and their content may play a role in fibre toxicity. To shed light on the role of trace elements in asbestos carcinogenesis, knowledge on their concentration in asbestos-mineral fibres is mandatory. It is possible that trace elements play a synergetic factor in the pathogenesis of diseases caused by the inhalation of mineral fibres. In this paper, the concentration levels of trace elements from three chrysotile samples, four amphibole asbestos samples (UICC amosite, UICC anthophyllite, UICC crocidolite and tremolite) and fibrous erionite from Jersey, Nevada (USA) were determined using inductively coupled plasma mass spectrometry (ICP-MS). For all samples, the following trace elements were measured: Li, Be, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Sb, Cs, Ba, La, Pb, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, U. Their distribution in the various mineral species is thoroughly discussed.The obtained results indicate that the amount of trace metals such as Mn, Cr, Co, Ni, Cu and Zn is higher in anthophyllite and chrysotile samples, whereas the amount of rare earth elements (REE) is higher in erionite and tremolite samples. The results of this work can be useful to the pathologists and biochemists who use asbestos minerals and fibrous erionite in-vitro studies as positive cyto- and geno-toxic standard references.
Show more [+] Less [-]Particle size and chemical constituents of ambient particulate pollution associated with cardiovascular mortality in Guangzhou, China
2016
Lin, Hualiang | Tao, Jun | Du, Yaodong | Liu, Tao | Qian, Zhengmin | Tian, Linwei | Di, Qian | Rutherford, Shannon | Guo, Lingchuan | Zeng, Weilin | Xiao, Jianpeng | Li, Xing | He, Zhihui | Xu, Yanjun | Ma, Wenjun
Though significant associations between particulate matter (PM) air pollution and cardiovascular diseases have been widely reported, it remains unclear what characteristics, such as particle size and chemical constituents, may be responsible for the effects. A time-series model was applied to examine the cardiovascular effects of particle size (for the period of 2009–2011) and chemical constituents (2007–2010) in Guangzhou, we controlled for potential confounders in the model, such as time trends, day of the week, public holidays, meteorological factors and influenza epidemic. We found significant associations of cardiovascular mortality with PM10, PM2.5 and PM1; the excess risk (ER) was 6.10% (95% CI: 1.76%, 10.64%), 6.11% (95% CI: 1.76%, 10.64%) and 6.48% (95% CI: 2.10%, 11.06%) for per IQR increase in PM10, PM2.5 and PM1 at moving averages for the current day and the previous 3 days (lag03), respectively. We did not find significant effects of PM2.5-10 and PM1-2.5. For PM2.5 constituents, we found that organic carbon, elemental carbon, sulfate, nitrate and ammonium were significantly associated with cardiovascular mortality, the corresponding ER for an IQR concentration increase at lag03 was 1.13% (95% CI: 0.10%, 2.17%), 2.77% (95% CI: 0.72%, 4.86%), 2.21% (95% CI: 1.05%, 3.38%), 1.98% (95% CI: 0.54%, 3.44%), and 3.38% (95% CI: 1.56%, 5.23%), respectively. These results were robust to adjustment of other air pollutants and they remained consistent in various sensitivity analyses by changing model parameters. Our study suggests that PM1 and constituents from combustion and secondary aerosols might be important characteristics of PM pollution associated with cardiovascular mortality in Guangzhou.
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